


The Fitbit Mystery

by NavajoLovesDestiel



Category: Supernatural
Genre: Anal Sex, Bottom Castiel (Supernatural), Bottom Dean Winchester, Castiel in the Men of Letters Bunker (Supernatural), Confused Sam Winchester, Light Bondage, M/M, Porn With Plot, Sex, Shameless Smut, So much smut, Switching, Top Castiel (Supernatural), Top Dean Winchester
Language: English
Status: Completed
Published: 2019-10-23
Updated: 2019-10-23
Packaged: 2020-12-31 16:06:52
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 1,831
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21148451
Author URL: https://archiveofourown.org/users/NavajoLovesDestiel/pseuds/NavajoLovesDestiel
Summary: Sam thinks Dean and Castiel need to exercise more so he buys them fitbits. The results are surprising.





	1. Chapter 1

**Author's Note:**

  * For [KatelynDeveraux](https://archiveofourown.org/users/KatelynDeveraux/gifts).

> Written from a prompt from KatelynDeveraux and for the Pray4sammy Challenge.  
Many thanks to aliceintheburrows for her help!

Cas pushed Dean against the wall so hard, Dean went “oof!” He jumped up and wrapped his legs around Cas' hips and Cas put his hands under Dean’s ass, pulling the cheeks apart. He lowered Dean onto his cock. Dean let his head fall back against the wall and grabbed Cas’ shoulders. 

Dean began to raise himself up and jam himself back down on Cas’ cock. He moaned, and Cas kissed him. “You’ve got to be quieter or Sam will hear.”

Dean groaned. “We need to find a friggin’ case so we can get a motel room.”

Cas chuckled, and walked to the bed, effortlessly carrying Dean. Damn, he loved how strong his angel was!

Cas tossed him on the bed, and followed him down.

“I want to ride you.” Cas lay flat and Dean crawled over him, situating himself over Cas’ cock and slowly sliding down.

He rode Cas like Cas was a mechanical bull. Cas’ cock was thick and perfect, filling him just right. It slid over his prostate with every thrust. Cas bent his knees and thrust up every time Dean slid down and it was so good...

They’d been at it for almost an hour. Cas could control his orgasm with his grace, and Dean had already come twice. He wasn’t sure he could come again, but he was up for trying.

Cas grabbed him and rolled over. Dean wrapped his legs around his hips and Cas pounded into him. “Fuck, Cas, will you cum already? I’m getting a cramp…”

Cas chuckled in that low way he had and kept pounding, but Dean could tell he was letting himself go. He knew every tell his angel had.

Cas groaned in his ear and came. The feeling of it filling Dean sent him over the edge again, and his cock squirted out one little stream. He felt like his balls were completely empty.

Cas snapped his fingers and they were clean. Dean passed out.

The next morning, Dean was walking funny. He hobbled into the kitchen, grabbing a cup and filling it with coffee.

“What’s with you today, man?” Sammy was frowning at him. Cas was standing behind him with a smirk on his face.

“Yeah, just got a hellacious cramp in my thigh last night. Still sore.” He went and sat down with a frown at Cas.

“You are so out of shape!” Sam sat down at the table with his patented bitchface. “You never get any exercise. You just eat crap, drink too much and lay around.”

Dean took a drink of his coffee. “I’m in great shape, Sammy. Don’t you worry about me.”

Sam shook his head. “I gotta worry. I depend on you. You need to get in shape.” 

He turned to look at Cas. “You too.”

Cas frowned (and Dean absolutely didn’t think it was adorable). “Me? I’m in perfect shape. I’m an…”

Sam interrupted him. “Don’t give me that ‘I’m a celestial wavelength’ crap. It wouldn’t hurt you to exercise a little. I swear, you two…”

Dean chuckled and Cas tilted his head.    
“”Let it go, Sammy. We’re fine.”

A couple of days later, Sam walked into Dean’s man cave, where he and Cas were watching Tombstone for the hundredth time. 

“I’m gonna go into town. I have some errands, and I’m gonna catch a movie. I’ll be gone for about four hours. Get up and do something while I’m gone, will ya?”

Dean waved a hand. “Yeah, yeah, Sammy. Have fun.”

Sam shook his head in frustration.

When they heard the front door slam shut, Dean turned off the movie. 

“Hear that, angel? We got four hours! We can be as loud as we want.”

Cas smiled. “I’m your huckleberry.” He waved a hand. They were naked. Dean grinned. “I love when you do that. A real time saver. Now, come here.”

Dean grabbed Cas. “I’m gonna fuck you until you scream.” He turned Cas around and bent him over the back of the couch. “Do your magic.”

Cas lubed himself up with a flick of his wrist. Dean could see the glisten on Cas’ hole and he grinned. “Another time saver.” 

He grabbed Cas by the hips and pushed in. They both groaned.

“God damn you’re tight. You use your grace to be that tight?”

Cas didn’t answer. 

Dean sunk in as far as possible and began to fuck Cas hard and fast. He gripped Cas’ hips tight enough to leave leave bruises if Cas didn’t wink them away when they were done.

Dean loved to see his cock disappear inside Cas. He watched it intently. “You look so good, angel, taking my cock. I wish I could last as long as you do. You and your fucking grace…”

Cas pushed back against him and clenched down on his cock, and Dean lost the ability to word.

Now they were in the shower, and Cas was fucking Dean. Dean had his arm up on the tile and his head on his arm. His other hand was gripping Cas’ hip as Cas slowly fucked in and out. They had fucked in the man cave, the kitchen and now, needing to get clean before Sam got back, in the shower. Cas didn’t use his grace, they were under a time constraint. 

After Cas came, they washed off and got dressed again. They were on the couch, watching another movie when Sam got home.

Sam walked in and frowned. “You two have been here the entire time I was gone? Jesus Christ, you’re lucky you can even walk. I’d think your legs would atrophy.”

Dean flipped him off. He jumped when a small box landed in his lap.

“What’s this?”

Sam walked in front of the TV. “It’s fitbits for the two of you. I ordered them off Amazon. I hope, when you see just how sedentary you are, maybe you’d get up off your ass and get some exercise. And I’m going to check them every day.”

Dean opened the box. There were two fitbits for their wrists. He tossed one to Cas, who squinted at it.

“Better put it on, Cas. When Sam gets an idea in his head, he’s like a bulldog with it.”

They put them on and went back to their movie.

Having had mind-blowing sex for hours that day, they just went to sleep that night.

In the morning, Sam grabbed Dean by the wrist and looked at his fitbit.

“See? You haven’t done a damn thing.” He looked at Cas’ while Cas squinted at him. “You either. Cas, I’m expecting you to be better than this. Go, exercise.”

Dean drank his coffee and Cas sat down next to him. Cas cocked an eyebrow at Dean, who just gave a small shake of his head.


	2. Chapter 2

Cas was on the bed, face down and ass up. His wrists were tied to his ankles. Dean was plowing in and out of him. Sweat rolled off Dean like a river. He’s been at it for twenty minutes. Every time he got close to coming, he’d stop and grab the base of his cock, making a circle of his index finger and thumb and squeeze until the feeling passed.

He fucking loved edging himself and Cas at the same time. Cas was under strict orders not to come.

Cas was whining, which Dean also loved. “Please, Dean, I can’t anymore.”

Dean slapped Cas’ ass. “Sure you can, angel. Use your grace.”

Cas growled, “That is a poor use of my grace, Dean.”

Dean laughed and shoved in harder. “Yeah? And fucking me for hours is?”

Truth was, his abs were screaming at him and he really was in danger of getting a bad leg cramp. He let himself go and soon, he was coming. He gave Cas permission to come as well.

They both yelled with the intensity. Luckily Sam was gone, or Dean would never have started this. He collapsed on the bed, and began to untie Cas.

He drank some water, feeling dehydrated. Cas cleaned them up and they went to sleep.

The next morning, Sam grabbed Dean’s wrist and looked at his readings.

“Dean, what did you do last night to get these readings? It looks like you almost killed yourself.”

Dean yawned and scratched his balls. “Not a damn thing.”

Sam looked incredulous. He checked Cas’ fitbit and it read some activity as well.

“Well, you had to have done some exercising.”

Dean shook his head. “I’m telling you, Sam, we didn’t do anything any different than we do every night.”

Sam looked at Cas, who nodded in agreement. 

“Whatever.”

Weeks went by, and Sam couldn’t explain the readings on their fitbits. It showed vigorous physical activity, but he never saw them exercise at all, and they steadfastly maintained that they weren’t.

Dean lay naked on the map table. His legs were slung over Cas’ shoulders, and Cas was bent over him, fucking.. He was going slow, but every thrust into Dean was hard, punching grunts out of Dean every time.

“Please, Cas… faster… please...I can’t…”

Cas leaned over more, which lifted Dean’s ass off the table. “You’ll take what I give you.”

Dean almost sobbed. But even this was fantastic. There still wasn’t anything like being fucked by an angel… his angel. 

Sam was on a hunt with Eileen, and they had been fucking almost non-stop since Sam left. It was day three of their fuckfest.They had done the deed in the kitchen, the shower, on Dean’s bed, on Cas’ bed, in the man cave and now on the map table. They switched off, taking turns with who topped and who bottomed. It had been magnificent.

But Sam was on his way back, so this was the last time they would be able to fuck so openly for awhile. 

Neither of them heard the door creak open, too lost in each other.

“OH my  _ GOD _ !” the sound of Sam screeching was like chalk on a blackboard.

Cas gave one last thrust and pulled out. He waved a hand and cleaned them both up. He put his hands in front of his junk and turned to face Sam, who was walking slowly down the stairs with his hands over his eyes.

Dean jumped up and grabbed his jeans. When he had them on, he handed Cas his pants.

“Okay, Sam, you can open your eyes, ya dork.”

“Dork?  _ I’m _ a dork? I’m scarred for life. There isn’t enough bleach on earth to take away that memory.”

Cas chuckled. “It’s a perfectly natural human thing, Sam.”

Sam nodded but still had ducklips. “Yeah, I know. Wait… do you do this all the time?”

Dean grinned. “We do get pretty damn busy.”

Sam suddenly looked like he had an epiphany. “So that’s what is going on with your fitbits! I couldn’t figure the readings out. Ew. Ew, ew ew.”

He ran out of the room, hearing Dean and Cas laugh all the way to his bedroom. 

“Ew.”


End file.
